1. Field of the Invention
This invention relates generally to lathes, and more particularly to wheel securing devices for turning of railroad wheels on a lathe.
2. Prior Art
Wheel maintenance is an important item for the safety and efficiency of railroads. The tread or rolling surface is originally machined with close tolerances, to a specific contour. This contour consists of a tread which gradually tapers outward from its axis from the front face of the rim of the wheel to a radially outwardly extending flange which culminates in the flange edge of the wheel. This surface engages the rail in a manner which causes maxiumum wear in the transition area between the front face of the rim and the flange. Historically, worn railroad wheels have been reclaimed by machining the wheel to a new diameter at which there is sufficient material to restore the original contour. This process must be performed equally around the wheel tread circumference of both wheels in a set. There is, of course, minimum requirements for flange thickness and wheel diameter which limit the number of times a wheel can be reclaimed on a lathe.
The wheel turning lathes of the prior art are subsrtantially manually adjusted. The wheel securing elements of the prior art have their bases held in generally radially directed T-slots that are milled in the surface of the rotatable face plate. Large grooves or T-slots are not only expensive and time consuming to produce in the face plates of a lathe, but they also weaken the structure of the plate. Since the wheel securing elements in the completed prior art face plates are adjusted manually and individually, it increases the machine down-time.
An improvement in the lathe gaging of railroad wheels was shown in U.S. Pat. No. 3,938,254, and assigned to the assignee of the present invention.
An object of the present invention is to provide automatic adjustment of the railroad wheel securing devices in wheel lathe machines.
A further object of the present invention is to provide a railroad wheel securing mechanism which will function for any diameter railroad wheel.
A still further object of the present invention is to provide a railroad wheel securing mechanism that safely counters the forces incurred in the wheel as the tread is being machined.
A yet another object of the present invention is to provide a railroad wheel securing mechanism that is less expensive, stronger and more efficient than prior art railroad wheel lathe securing devices.